HONDA CR500

[r1-daz]

Ok,here goes.....

I've put a 1989 CR500 motor in a Kawasaki KR1s frame,come to turn it over ,no spark.

Sent the stator coil to West Country Windings to be checked and comes back with the all clear.

Put a multimeter on the stator and pulse pick up and it gives the correct readings,check the CDI voltage output to the ignition coil,gives the correct readings,but still no spark.

Tried the brand new Honda ignition coil on a Honda cr80,works fine.

Disconnected the kill switch to take that out of the equation,fitted a new plug cap and spark plug and fitted 3 extra earth wires to the bare metal frame from the CDI and coil,STILL NO SPARK!!!!!!

Only thing i suspect now is the CDI box,but everyone says they don't pack up

The only sure fire way of sourcing the problem is to have a running CR500 next to it and start swapping parts over but i don't know anyone with one.

Any thoughts or suggestions would be greatly appreciated.

Cheers Daz (nearly bald due to pulling my hair out!!!)

PS: A couple of piccys of the troublesome beast.(Note the stinger coming out of the seat unit........trick!!!!)

[dizzyr1]

Mint idea of cr500 in kris frame,

just because everyone says the cdi's dont fail does'nt mean they dont, however just as a far out idea, is the pick up wired in right ( two small wires, will result in no spark, but as engine turns rev counter fluctuates) did it on aprilia had same effect, reversed it and hey presto, (a rabbit climbed out of the barrells, what the hell am i drinking)

Find your local off road track and ask around or do a search for the folks in america that build brand new cr500's in 250 frames (dealer in brum) because they do know their sh*t

[Sean]

i know it sounds silly but i had the same problem with my RD, turned out to be a faulty brand new NGK spark plug to blame, put the old one in, and hey presto solved. I've replaced it now btw.

Edit: just read your post again, you have allready tried it

[r1-daz]

EUREKA!!!!!

I've fixed it,sparks like Blackpool illuminations now.

Thanks for your advice guys,it was the swapping of the 2 wires on the pick up that got me thinking.You can't get them wrong because they're all colour coded and block connectors,but then i realised something.

You'll piss yourself when i tell you what the problem was,first of all let me explain that i don't have a kick start on it yet because i need to extend the shaft past the frame rails so what i've been doing is putting it on a paddock stand and putting it in gear with the spark plug out and turning the back wheel...no problem except i was turning the wheel backwards which i didn't think would matter.....WRONG!!!!! A 2 stroke with CDI will not fire in reverse if the pick up coil and stator coil are less than 180 degrees apart.

A quick explanation of how CDI works:

4 magnets in the flywheel positioned north/south/north/south (+/-/+/-) go past the stator coil and produce about 14volts AC,which goes to a capacitor in the CDI box which charge up to about 100 volts DC,when the notch on the outside of the flywheel comes round to the pick up coil it sends about 0.5 volts to the CDI which tells the trigger to release the 100 volts in the capacitor to the Ignition coil which then boosts the voltage to anything over 20,000 volts(it needs to be this big so it can jump the gap on the spark plug),

However,normally the flywheel would do 270 degrees from the stator to the pick up,but by turning the engine over backwards its only 90 degrees so the CDI wasn't charging enough before the pick up was telling it to release to the coil.

Hope i havn't confused you all.

In simple terms "THE TWAT WAS TURNING IT OVER THE WRONG WAY!!!!"

[blow_away]

Great looking project, sounds madder than a bucket of spiders

Keep us informed of progress

[TriGGer]

bejesus ! that things gonna have teeth !

[r1-daz]

That front cradle holding the engine up is TITANIUM.

I work for a Motorsport company making bits for F1 cars and that piece of titanium was just lying around,so i thought if Lewis Hamilton don't want it ,i'll have it!!!! (shit, i hope his front suspension don't drop off now).

The KR500 now weighs about the same as a bag of crisps......

Having the exhaust chromed next week then i'll fit the radiator, so the next photos will be posted in the project section.

Thanks again for your help

Daz

[raccoon rebuilds]

good looking project you have there,

[Acid]

loving this project

Cr500 power rocks

me bias never

[intra]

That looks like a fucking laugh and a half right there man. She'd be wicked fun around a tight little track.

[r1-daz]

That looks like a fucking laugh and a half right there man. She'd be wicked fun around a tight little track.

I'm actually going to put it on the road!!!!(or as i like to call it 'The Queens race track!!)